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Snakes

Diamondback Watersnake

Nerodia rhombifer

Across the regions where it's common, the Diamondback Watersnake peaks from March to July.

Shows up in 10 ecoregions and 9 states

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Snakes

Diamondback Watersnake

Nerodia rhombifer

Look, don't take. Many states regulate collecting reptiles and amphibians. Photograph it, log it on iNaturalist and leave it where you found it.

Description

Nerodia rhombifer, commonly known as the diamondback water snake, is a species of nonvenomous natricine colubrid endemic to the central United States and northern Mexico. The diamondback water snake is predominantly brown, dark brown, or dark olive green in color, with a black net-like pattern along the back, with each spot being vaguely diamond-shaped.Wikipedia ↗

Habitat

The diamondback water snake is one of the most common species of snake within its range. The diamondback water snake is found in the central United States, predominantly along the Mississippi River valley, but its range extends beyond that.Wikipedia ↗

When it's active

Adults breed in the spring, and gravid females give birth in the late summer or early fall.Wikipedia ↗
B. P. White · CC BY-SA 4.0

Often mistaken for

Northern Cottonmouth, Florida CottonmouthMany scientists dislike the use of the term water moccasin since it can lead to confusion between the venomous cottonmouth and nonvenomous water snakes. Wikipedia ↗Nerodia fasciata is often mistaken for venomous cottonmouths (Agkistrodon piscivorous) despite the differences in their physical appearance. Animal Diversity Web ↗Cottonmouths vs. watersnakes →

When and where it's active

Each row is its own calendar, counted from records in that area. Seasons shift by place.

PeakShoulderQuiet

Ecoregions

States

About the Diamondback Watersnake

When is the Diamondback Watersnake most active?

Across the regions where it's common, the Diamondback Watersnake peaks from March to July.

Where does the Diamondback Watersnake live?

It has enough records to show in 10 ecoregions and 9 states, including Arkansas, Illinois, Kansas, and Louisiana.

What does the Diamondback Watersnake look like?

It's often confused with the Northern Cottonmouth and Florida Cottonmouth.